Refrigerating apparatus



July 30, 1935. H. E. ROSEBROOK 2,009,975

REFRIGERATING APPARATUS Filed Aug. 9, 1953 3 Sheets-Sheet} July 30,1935. H. ROSEBROOK REFRIGERATING- APPARATUS Filed Aug. 9, 1933 3Sheets-Sheet 3 I 17 2065557".- 170272641 fi0a@5r00% Patented July 30,1935 Homer E. Rosebrook, Greenville, Mich, assignor to Gibson ElectricRefrigerator Com, a corporation of Michigan 2 Application August 9,1933,Serial No. 684.421

11 Claims. (Cl. 62126) A This invention relates to improvements in .re-

frlgerating apparatus and method and more especially relates totheevaporator or vaporizer.

-My' invention is particularly applicable to refrigerating apparatus ofthe so-called, floodedtype in which lubricating oil is mixed with therefrigerant and separated therefrom by a difference in specific gravity.Such separationis usually obtained in the evaporator by allowing the oilto float up to the top of the liquid refrigerant.

Heretofore, however, such separation has caused the oil to form in alayer on the surface of the liquid refrigerant and this has interferedwith or lessened the evaporation or boiling of the refrigerant.

' Among the features of my invention is the provision of means andmethods for drawing the oil off of a portion of the surface of theliquid refrig erant so that boiling at such peded.

portion is not im- Another feature is the provision of means and methodfor concentrating oil on a portion of the surface of the liquidrefrigerant while producing boiling'under said portion, whereby theformation of said concentrated oil into a film'is prevented and boilingof the refrigerant is not ret-arded.

Other features and advantages of my invention will appear more fully asI specification.

proceed with my drawings,-

Fig. 1 is a diagrammatic view of refrigerating apparatus; Fig. 2 is avertical sectional view of the evaporator; Fig. 3'is a view taken asindicated by the line 3 of Fig. 2; Fig. 4

is a view similar to Fig. 2 showing a modified form of evaporator;

Fig. 5 is a view similar to Fig.

modification; and Fig. 6 is a view taken as indiv cated by theline 6 ofFig. 5.

2 showing another In Fig. 1 which is merely diagrammatic I have made noattempt to show a ll thedetails of a complete refrigerating apparatus asthese are all well known in the art. I have left out entirely, forexample, thethermostatic control ordinarily employed as a showing ofthis is not necessary to illustrate myinvention. In Fig. 1, I0illustrates the usual compressor, H the motor therefor, l2

the condenser, and I3 a float controlled valve for controlling the flow'of refrigerant from the-comprossor to the evaporator I4.

' example, may be designed to rrigerant to the evaporator.

In the apparatus I have sho The valve I3, for pass only liquid rewn arefrigerant 20 inlet pipe for the vaporizer. The pipe 3| leading fromthevaporizer to the compressor I shall refer to as the outlet pipe and thispipe is adapted 1 to withdraw oil and gaseous refrigerant from theheader 40. For this purpose its end is preferably bevelled 0r slanted,as shown, and high enough. so it will get oil and gas, but not liquidrefrigerant. I I In Figs. 1 to 3 I have shown a vaporizer with twosections here shown in the formof two'headers 40 and 4| withtheusualrisers 42 and 43, respectively. 'I'hisvaporizer, in its'generalconstruction, may'resemble those now in common 2 use. For example, itmay be made of corrugated sheet metal spot welded to provide thenecessary circulation and communication. The lower" ends of the risers42 maybe connected together and likewise the lower ended the risers 43,25

but there is no connection between the lower ends 'of the risers 42 and43.

The inlet pipe for conducting lubricant oil'and refrigerant to thevaporizer may enter at the bottom of the risers 43 as indicated by 30 orit may 80 the header 4| at the normal level 46 of the liquid refrigeranttherein. This tube is led downwardly (here shown as inside of one of therisers 43) and its lower end 50" enters the bottom of the risers 42.

As the refrigerant and oil enter through the pipe 30 or 30' it flowsinto the header 4| filling this header to the level 46, and thenoverflowing into the tube 50'. Since the upper end 50 of the tube 50terminates at the-level of the liquid .45

refrigerant there is no blanket of oil lying on top of the liquidrefrigerant in header. As the liquid comes in, it overflows through thepipe 50 into the bottom of the risers 42. 'Down this tube 5|) the oiland some refrigerant will run 50 practically all the time. As the liquidrefrig-' erant and oil run down the tube 50, gathering boiling, it comesup the risers 42 and breaks up any film of oil tending to'form in theheader 40.. This film tending to, form and being broken up by theboiling I have attempted to indicate by 2I. As a result of thisdisturbance the retardation of the boiling by the oil is eliminated orlessened.

the risers I42 and I43 correspond to the riser 42 and 43. lhe pipe I50,corresponding to the pipe 30, leads from the liquid level in chamber Ito the bottoms of the risers I42. When these corresponding parts arenoted the construction and operation of the device of Fig. 4 will beclear. In Fig. 5, I have shown a vaporizer in which the section of thevaporizer from which the refrigerant is withdrawn, is relatively small.This section, for example, may be in the form of a round tube separatefrom the rest of the vaporizer. As shown in Fig. 5, the two sections ofthe vaporizer are indicated by 240 and 24l, the latter section beingprovided with the usual risers 242 and 243, said risers communicating attheir lower ends. The inlet pipe 230 enters at the bottom of the risers243 of the section 24I. 250 indicates a pipe leading from the liquidlevel in section 2 to the bottom of section 240. The construction andfunction of this pipe is the same as or similar to those of pipe abovedescribed. In the form of Fig. 5, 23I is-the outlet pipe.-

While I have shown and described certain embodiments of my invention, itis to, be'understood that it is capable of many modifications. Changes,therefore, in the construction and arrangement may be made withoutdeparting from the spirit and scope of the invention as disclosed in theappended claims, in which it is my intentionto claim all noveltyinherent in my inven-- tion as broadly as possible in view of the priorart. What I regard as new, and desire to secure by Letters Patent, is: i

1. An evaporator for refrigerating apparatus employing in a-floodedsystem a mixture of liquid refrigerant and lubricating oil adapted toseparate by differences in specific gravity, including; two sectionsforcontaining refrigerant, each having a vapor space' above the level ofthe liquid refrigerant therein; means for introducing a mixture ofliquid refrigerant and oil into one of said sections; a conduit fordrawing oil from the surface of the liquid refrigerant in said-section,said conduit also permitting overflow of liquid refrigbelow the surfaceof liquid therein; and means for withdrawing oil and gaseous refrigerantfromsaid other section.

2. An evaporator for refrigerating apparatus employing in a floodedsystem a mixture of liquid refrigerant and lubricatingoil adapted toseparate by differences in specific gravity, including; two sections forcontaining refrigerant, each having a vapor space above the levelof theliquid refrigerant therein; means for introducing a mixture of liquidrefrigerant and oil into one of said sections, below the surface oftheliquid refrigerant therein; a conduit for drawing oil from thesurface of the liquid refrigerant in said section, said conduit alsopermitting overflow of liquid refrigerant, said conduit leading to theother section below the surface of liquid therein; and means forwithdrawing oil and gaseous refrigerant from said other section.

3. An evaporator for refrigerating apparatus employing in a floodedsystem a mixture of liquid refrigerant and lubricating oil adapted toseparate by differences in specific gravity, including; two sections forcontaining refrigerant, each havmg a vapor space above the level of theliquid .refrigerant therein; means for introducing a mixture of liquidrefrigerant and oil into one of said sections; a conduit for drawing oilfrom the surface of the liquid refrigerant in said section, said conduitalso permitting overflow of liquid refrigerant, said conduit leading tothe other section below the surface of liquid therein; and means forwithdrawing oil and gaseous refrigerant from said other section.

4. An evaporator for refrigerating apparatus employing in a floodedsystem a mixture of liquid refrigerant and lubricatingoil adapted toseparate by differences in specific gravity, including; two sections forcontaining refrigerant, each having a vapor space above the level of theliquid refrigerant therein; means for introducing a mixture of liquidrefrigerant and oil into one of said sections, below the surface of theliquid refrigerant therein; a conduit for drawing oil from the surfaceof the liquid refrigerant in said section, said conduit also permittingoverflow of liquid refrigerant, said conduit leading to the othersection below the surface of liquid therein; and means for withdrawingoil and gaseous refrigerant from said other section.

5. The method of operating refrigerating apparatus of the flooded typecontaining oil and refrigerant adapted to separate by differences inspecific gravity, including, concentrating oil on a part of the surfaceof the liquid refrigerant in the vaporizer, and producing localizedboiling of refrigerant under said oil, whereby said 011 is broken up andprevented from forming a film.

6. The method as claimed in claim 5, in which the oil as it is broken upis withdrawn with gaseous refrigerant.

7. The method of operating refrigerating apparatus of the flooded typecontaining oil and refrigerant adapted to separate by differences inspecific gravity, including, concentrating oil on a part of the surfaceof the liquid refrigerant in the vaporizer, drawing liquid refrigerantfrom a part of the surface of the liquid refrigerant in the vaporizer,passing said drawn liquid refrigerant through a relatively warm part ofthe vaporizer to induce boiling of the refrigerant, and discharging saidboiling refrigerant under said first mentioned concentrated oil.

8. The method of operating refrigerating apparatus of the flooded typecontaining oil and refrigerant adapted to separate by differences inspecific gravity, including, concentrating oil on a part of the surfaceof the liquid refrigerant in the discharging said boiling refrigerantunder said first mentioned concentrated oil.

9. An evaporator for refrigerating apparatus employing in a floodedsystem a mixture ofliquid refrigerant and lubricating oil adapted toseparate by differences in specific gravity, including;-

two sections for containing refrigerant, said sec- I tions beingsubstantially on the same level, each having a vapor space above thelevel of the liquid refrigerant therein; an inlet pipe entering one ofsaid sections below the liquid level; an overflow pipe leading from theliquid level in said section to a point below the liquid level in theother section; and an outlet-pipe with its end just above the level ofthe liquid refrigerant in said other section. a

10. The method of operating refrigerating apparatus of the flooded typecontaining oil and refrigerant adapted to separate by difierences inspecific gravity, including drawing oil from a part of the surface ofthe liquid refrigerant in the vaporizer to lessen retardation of boilingat said part of said surface by the presence of oil thereon,transferring said oil to another-part of the surface of the liquidrefrigerant, and withdrawing oil and gaseous refrigerant from said otherpart through a single conduit. v

1 1. The methodof operating refrigerating appa-.

of oil thereon, transferring said oil to another part of the surface ofthe liquid refrigerant, and withdrawing oil and gaseous refrigerant fromsaid other part through a single conduit.

HOMER E. ROSEBROOK.

